Answer:
trapezoid
Explanation:
A right trapezoid has 2 parallel sides and 2 adjacent right angles.
In geometry, the base of a prism is the actual shape.
So the base of a triangular prism is the triangle, similarly the base of a pentagonal prism is the pentagon, etc.
Therefore, the base of a trapezoidal prism is the trapezoid itself.
If the prism is cut parallel to the base, then the cross section will be the same shape as the base. So in this case, it will be a trapezoid.